1. Field of the Invention
The present invention is directed to the field of high intensity lighting devices and more particularly to the area of lamp plug assemblies that are removably inserted into a sealable and reusable reflector housings.
2. Description of the Prior Art
Conventional sealed beam headlamps, as utilized in U.S. manufactured automobiles, typically utilize a tungsten filament embedded in a molded glass reflector portion. The reflector portion is fuzed to a diffusion lens component. The resultant enclosure is evacuated and permanently sealed. In the event of a lens crack or filament failure, the entire sealed beam unit, including the reflector, lens and filament must be replaced. In order to keep replacement prices within reason, sealed beam headlamps are government regulated and consequently supplied to the market in a very few standard sizes and shapes. Accordingly, automotive styling, in the area of headlamps, is severly restricted, from an aerodynamic standpoint, due to the necessity of utilizing these standard sealed beam units.
Some European vehicles have, in the past, utilized stylized removable lenses with reflectors and replaceable lamps for headlamp units. However, due to the fact that the lenses were generally removable from the body moldings, dirt and moisture eventually was able to enter the interior of the unit and degrade the amount of light reflected out.
Some halogen lamps, currently on the market, are of a hermetically sealed variety in which a lens is sealed to a reflector. The reflector contains a rear opening for accepting a quartz halogen filament bulb, but a glass balloon is integrally formed onto the reflector so as to provide a transparent interface between the halogen bulb and the sealed reflector lens enclosure. The interior of the sealed enclosure is generally filled with a helium atmosphere to compensate for pressure changes, due to heat from the filament bulb. The problems which occur in these commercially available halogen lamps is due to the fact that dirt and moisture tends to enter the rear opening of the reflector between the quartz halogen filament bulb and the glass balloon. Therefore, over time, the radiation from this type of lamp will deteriorate until the bulb is removed and both the bulb and balloon are cleaned.